The worst drought in decades is expected, over the next few months, to continue choking a large area of the Plains and Rockies that missed the soggy remnants of Hurricane Isaac, according to the National Weather Service's Seasonal Drought Outlook released Thursday.

But those lingering rain bands from the hurricane did provide welcome moisture to the Midwestern states that were previously the epicenter of the drought, soaking states like Missouri, Illinois and Indiana with 2 to 6 inches of rain, the Agriculture Department's U.S. Drought Monitor also reported Thursday. Most of Missouri has been downgraded from being in exceptional or extreme drought to being in severe drought. Almost all of Illinois and Indiana are now in the severe or moderate category.

Still, the drought's severity was upgraded through much of the Central and Southern Plains - an area that stretches from southern South Dakota to northern Texas and has been suffering from triple-digit temperatures as well as lack of rain. Parts of South Dakota fell into exceptional drought, and that categorization expanded in large parts of Oklahoma, Kansas and Nebraska as well.

Forecasters say that this region is moving to a climatologically drier time of the year, meaning that the drought will likely intensify in the coming months.

Overall, 62.89 percent of the continental United States remained in moderate to exceptional drought, an improvement of less than a half a percent from last week, according to the Drought Monitor.

All this has meant that, despite the downpours of Hurricane Isaac, the desiccated regions of the country still had ponds too shallow to water cattle, fields too dusty for feeding and crops beyond the point of salvage.

The rains were "too late to bring much improvement for summer crops," said Brad Rippey, a meteorologist with the Agriculture Department. "We're kind of looking ahead now to winter wheat planting."

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